Hello I’m located in Nassau, Bahamas. While living in the islands has its perks, the not so obvious down side is that it is impossible to find trades people skilled in anything but tar paper shingles.

There may be people here that are qualified but with more hotels going up than you can shake a stick at those guys are not available.

I mention this because I posted a question a couple days ago but then upon reading it, I imagine it does seem a bit forward. I didn’t want to bump that thread so I’ve posted anew. But just so you guys will know, when I ask a question as a do it yourselfer, I’m not trying to take bread out of some contractor’s kid’s mouth.

I have a corrugated roof that flows into a valley(which is up against another building) lined with EPDM. The water then has to travel sideways 18 ft, to get off the roof.

The problem is, water is getting under the bottom of the metal and traveling back up. There is 3 ft of EPDM under the bottom section of the metal but water gets in.

This issue developed when we put the metal roof on top of a corrugated fiberglass roof that had problems in other sections. The original roof had a 30" EPDM valley with 16" of EPDM under the corrugated fiberglass roofing. The guys that put on the new roof left just a 16ÃƒÂ¢Ã¢â€šÂ¬Ã‚

You’re probably right. Is the second row supposed to be lapped center of the previous row? If not how is it supposed to be done?

I figure I’m going to have to have the first row cut back to where the original roof stopped leaving a 30" EPDM valley; so the best first step is to take up the first row and replace them with pieces cut the right length (leaving the valley 30") and make sure the new sheets are lapped properly.

boyblue you have a tough roof design to keep water tight. Corrugated metal is not intended to be used in this application where water can flow up and underneth. Don’t waste your money trying to repair it you will be just be throwing good money after bad. Tear off the metal and have a white tpo roof system installed with a proper roof to wall detail.Also the white will reflect the heat and make your home more comfortable. This is not a very large job. It should not be that hard to get the word out at a local hotel project to get a roofer to do the job on the side. There is someone always looking for side work. Check the local gin mill after working hours. Many roofers ane hard workers but are also hard drinkers.

Man, now that you mention it, that’s probably the best course of action. The thing is, additional weight from 5/8 plywood may be an issue. The only support for this roof is the exterior walls. Is there an alternative product that does not weigh as much.

Also, what if we went up 4 or 8 feet with the EPDM would that be enough to avoid the backwash? How would you handle the transition from metal to EPDM. Should they let the membrane come over the filler strip (under the end of the metal roof) or should they put the filler strip on top of the membrane and then use calking to seal up everything?

boyblue, help me understand what you mean by the only support for your roof is the exterior walls. What type of framing does your roof consist of? For example a roof may have a 2x4 rafter system that is 2 ft. on center(or spaced 2 ft. apart). What type of decking is under the metal or are there just puriins. I am not familiar with the building codes in the bahamas as far as load restrictions or being properly built in the first place. As far as backwash 4 ft back would be far enough.The problem is tying the single ply into the metal. The profile of the metal makes it very difficult to join the two. There is no “proper” way with this type of metal. If you choose to do the repair run the epdm UNDERNEATH the meatl at least 2 ft. As far as the transition buy tubes of water cut off or water stop and seal and seal underneath the metal and fill all the gaps so water can’t get underneath. This water stop is what we use to seal drains on a flat roof. I would not call this a proper installation but it will do the trick.Run the epdm up the wall and use a termination bar to terminate your detail. The following companies have a spec book online to help- Firestone ,Carsile or JM.

The wall in this 1st photo is the right side of our store (notice how it goes off in a 45Ãƒâ€šÃ‚Â° direction at the back). The left side of the store is the wall of another building.

Our roof hangs from one building to the next with a span of only 10ft (in the front section). This section has no problems.

If you can imagine this second picture being taken from where the wall (in the 1st photo) turns, the measurement from that point, down to the building at the back is 38ft. The measurement from the right corner (2nd photo) to where the roof meets the other wall (not shown) is also about 38ft.